The invention relates to a central circuit arrangement for motor vehicles for the central connection of electrical components, such as fuses, switching devices, electronic controls for electrical loads and the like, and including a plate-like layered packet of conductors which is composed of flat printed circuit boards that are stacked on top of one another in different planes and are separated from one another by insulating plates.
Such a central circuit arrangement essentially performs a distributing function in order to supply the electrical loads of the motor vehicle, such as, for example, lights, windshield wipers, blinkers and the like, with electrical voltage by way of conductor strands and wiring harnesses, so as to monitor the operational readiness of the loads, detect and indicate possible faults and, if necessary, interrupt faulty current paths. The actuation of the electrical loads is here effected by way of switching devices which are plugged in on the upper face of the central circuit arrangement as are the fuses for the load circuits. The socket pins engage in pin sockets attached to the uppermost flat circuit board of the central circuit arrangement. The wiring harnesses are here contacted on the underside of the central circuit arrangement by way of plug-in connectors. The plugged-in switching devices usually include an electronic control circuit with which the respectively associated electrical load is controlled.
The actual switching process for switching the load in and out is effected by means of a relay provided in the switching device. On the basis of the structural and manufacturing technology design of the flat printed circuit boards and the plug-in sockets, the central circuit arrangement is rigidly fixed with respect to its distributor function and can be set or adapted for different requirements only at above-average expense. Different configurations of flat printed circuit board circuitry can be realized only by means of particularly cost-intensive retooling which is not economically justified, particularly where small series are involved.
To overcome this drawback, DE-OS 3,525,085 already discloses a central circuit arrangement which includes a packet of conductors that are arranged on flat printed circuit boards which are stacked on top of one another in different planes and separated from one another by insulating plates. They are provided with plug-in sockets to receive plug-in portions disposed at components, with at least one conductor being disposed at at least one of the plug-in sockets so as to project beyond the conductor packet at at least one side thereof and to be selectively connected to at least one of the conductors of the insulated, stacked, flat printed circuit boards by way of a conductive bridge disposed on the side of the conductor packet. Since the conductors project laterally from the conductor packet, on the one hand, the number of possible circuit connections is greatly limited because of the amount of space available and, on the other hand, it is not possible to establish a direct electrical connection between opposing conductors that project from the conductor packet. Moreover, the known central circuit arrangement requires a conductor packet that is composed of a relatively large number of flat printed circuit boards and insulating plates because many free, unoccupied flat printed circuit board current paths are required to permit electrical connections to be made between one long side of the conductor packet and the other long side of the conductor packet.